blackbeauty

I've been doing a bit of reading on this forum about how to disable the AIR system in the 6E code on the 165 MAF ECM seeing as I do not have the system anymore. However I'm a little confused as to what exactly I need to do to disable this.

I'm using the expanded 6E definition with Tuner Pro and posts indicate that setting location 324 (IF temp < THRESH, DIVERT AIR) to the highest temperature possible will disable it. But, is that all I have to do?

Various posts hint at other things that can be altered relating to the AIR system but do they need to be done? Such things include setting location 454 (DIFF VALUE TO MAKE UP RICH/LEAN WINDOW When Air Div) to 0, then lowering all the numbers in the location range 459-473 by 102mV (the ARAP default). This last range seems to include the tables called...

UPPER ZERO ERROR REF FOR SLOW o2 R/L
LOWER ZERO ERROR REF FOR SLOW o2 R/L
Closed Loop Rich/Lean Threshold vs. Airflow
Fast O2 Rich/lean Threshold vs Air Flow
Low O2 Filter coef Vs Air flow

... with the last table requiring .102 being removed from the numbers in there.

Something else that interests me is the Rich/Lean Offset Vs. Coolant table, with some entries having the number 16. Do these get modified also?

So, what's the story? Do I need to do all the above or not, or do I need to do more?

blackbeauty

Nobody knows?

pandin

Go to Loc 31E in 6E and lower the rpm to 225. This will defeat the air injection system to the manifold.

You need not change anything else as the ECM will cause, the air pump air, to be diverted to the atmosphere, all the time (any rpm over 225). Original setting is 4425 rpm (exhaust back pressure exceeds air pump pressure above this point).

In a two valve system air is sent to the cat or the second valve then the second valve either sends to the manifold or vents to atmosphere.

The default is to the manifold. That is why the O2 constant table values are higher then 450mv, to compensate the O2 sensor for the extra air being injected into the exhaust system.

On divert, the offset of 100mv (Loc 454 6E), is subtracted from the O2 constants table values (Loc 459-473) to return to the "normal" range of 450mv from the .600 mv plus O2 constant table values.

1MeanZ

iTrader: (9)

Pandin, can you give me a bit more info here? I'm trying to get this added to my .xdf so I can modify it but I've always struggled with how to do this and never gotten right yet.

Here is the code..

LC31E FCB 177 ; 4425 RPM, Divert if RPM GT THRES & FOR
; LC31C sec's

I've attached the screen dump from tunerpro RT as well. This is where I get stuck. What constant or equation do I need to get this correct?

WillSpeedy

Blackbeauty you have a right hand drive 3rd gen? That kicks ***!

pandin

Got to the last fan setting Loc 310 and right mouse click to bring up the edit box, then insert new item by left mouse click on insert new item.

Click left click ok to new constant. Insert 31E at address (hex) spot.

Enter the name in place of "New Constant" at the top under title.

At the bottom is conversion left click on this and also on edit next screen. Add "*25" to the X. Left click ok, apply, and cancel.

Just double left mouse click on the Loc 31E and change the value from 4425 to 225.

Refer to the attached XDF, just remove the ".txt"

blackbeauty

Thanks for this.

So you're saying I don't need to play around with any of the other tables or constants I mentioned in my initial posting in order to disable the AIR system and its effects on the O2 sensor? Interesting. What is the significance of setting location 31E to 225RPM. How come not 0RPM?
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I sure do. There's several kicking around here in New Zealand and Australia. There are certain circumstances under which they must be converted to right hand drive.

Lucid

iTrader: (4)

You have to add a constant into Tunerpro

I know the link is here somewhere, JP86SS showed us how to do it
https://www.thirdgen.org/forums/diy-...6e-tuning.html

pandin

Each constant has a priority, this over rides that. So I guessed that RPM would over ride any of the other settings, and it would be the easiest to tell in the code, that something else wasn't checking this setting.

You can change (lower) the O2 constant tables and remove the 100mv offset but it is not required.

The constant (rpm) has to be lower then the lowest cranking speed, I set it above 0 in case math is used (can't divide by 0). Try it, may work.

I don't have real good code reading skills, so this is my best guess and it seems to work, no issues as to AFR suddenly changing.

1MeanZ

iTrader: (9)

Pandin, thanks for the help. I followed your instruction and it worked! I just needed to know the constant, and I had no idea how to figure that out. then I downloaded the xdf you posted...LOL. Anyway, that is a much more extensive definition file than the one I've been using off tunerpro's site. Now I'm off to follow Lucid's link and learn more about this and how to do it on a speed density setup since I have both now. (86 IROC and 91 TA). Thanks for the help guys.

blackbeauty

Thanks for the explanation and the help, it makes things much clearer.

89ROC-Z

iTrader: (7)

Sorry if im hijacking and also for a maybe stupid question. But how are you guys doing this? is it a laptop download (tunerpro?) and you need the correct cables? This sounds interesting and id like to give it a try.

RS Reaper

Yea you need Tunerpro and a cable to connect it to you computer and other stuff.
Here is the The Prom Tuning Guide Book and FAQ has everything that you need to know. enjoy

87transGTA

hey would this work for the tpi setup or is this just for the tbi cause id really like to get into the prom burning and tuning

RS Reaper

naaa it works on TPI, really TPI is more worth the time and most tuned cause a TPI engine has more power then a TBI.

Lucid

iTrader: (4)

Keep in mind this is a $6E XDF!!!!

You should not be doing this change unless your car is a emissions exempt and if you are in an emissions compliant area where you need air injection. (Except for like offroading etc)

The way I added the constant was:

-Click on the XDF dropdown menu
-Create new XDF Item
-Named it " Disable Air Injection Below Temp"
-changed units to Deg F (explain in a minute)

Disable Air Injection

Address (Hex) : 324
Size : 8 bit
Output type: floating point

Click on Conversion Table
Conversion: 1.350000 * X + -40.000000 (for Farenheit)
Argument: This item's raw data

Apply and save XDF with inputted information

Then you can go back and change the constant to 255 so it never turns on under 255 degrees (smart huh?) If anyone can verify this is correct by verifying that the hex address is pointing to the right constant please post up.

RBob

iTrader: (1)

Now that's funny, LOL.

RBob.

RS Reaper

OK are you telling me I'm wrong?
Cause from what I learned
-TPI is a batch fire system and have injectors located in every runner of the intake manifold.
-TBI has two injectors placed over the throttle body indirectly injecting through the intake manifold. This results in less power and imprecise amounts of air and fuel delivered to the cylinders

1MeanZ

iTrader: (9)

There are benefits and drawbacks to both TBI and TPI, and frankly, both systems are ancient by today's standards. He is laughing because either fuel injection system can be made to produce great power, one is not enough better than the other to warrant switching in many cases. There are a few TBI 350s and I think a few TBI 383s over on the TBI forum that would probably shock you.

blackbeauty

Now back on topic...

In re-reading this last paragraph, when diversion to the atmosphere happens, the offset and tables need to be set at their defaults otherwise everything is going to be out of calibration, right? I guess I should put those back to what they were.

This is probably quite a simple concept and I'm just over analysing...

RBob

iTrader: (1)

Once the AIR is set to divert all of the time you can just leave everything else alone. That way the calibration falls into place.

Or, you could also zero out the AIR O2 offset and then set the O2 window tables to what you (really what the engine) likes. This method tends to be better as there is one less calibration parameter to take into account.

It also eliminates the O2 offset and when it comes into play. One less thing to worry about.

RBob.

blackbeauty

Ah, I had wondered if that was the case or not. Thanks for that.

pandin

In the past there was quite a bit of discussion, about why the original Bins used such high O2 constants (swing points) Loc 459-473 (522-628 mv 6E), when the sensor was most accurate at 450 mv.

The only logic to prevail was that the ECM used the higher numbers, when adding air to the manifolds (right before the O2 sensor), to recalibrate the tune back to "normal". The added air (extra oxygen) was burned in the exhaust pipe and converter after the O2 sensor. This is a world that the engine lives in 90% of the time, so they likely made it "the default". One less computer/ECM subroutine to run.

Then when the air was shut off (diverted), the 100mv was subtracted to bring the tune to back in shape (closer to the 450 mv). This would be the "special case" and use the extra computer/ECM time. I am not a good source code reader, so there could still be discussion on this.

A large number of non tuning owners have had air pump break downs (broken belts) and have noticed no outward change to the car (engine codes or drivablity).